Parliament has used its legal powers to seize internal Facebook documents in an extraordinary attempt to hold the US social media giant to account after chief executive Mark Zuckerberg repeatedly refused to answer MPs’ questions.

The cache of documents is alleged to contain significant revelations about Facebook decisions on data and privacy controls that led to the Cambridge Analytica scandal. It is claimed they include confidential emails between senior executives, and correspondence with Zuckerberg.

Damian Collins, the chair of the culture, media and sport select committee, invoked a rare parliamentary mechanism to compel the founder of a US software company, Six4Three, to hand over the documents during a business trip to London. In another exceptional move, parliament sent a serjeant at arms to his hotel with a final warning and a two-hour deadline to comply with its order. When the software firm founder failed to do so, it’s understood he was escorted to parliament. He was told he risked fines and even imprisonment if he didn’t hand over the documents.

“We are in uncharted territory,” said Collins, who also chairs an inquiry into fake news. “This is an unprecedented move but it’s an unprecedented situation. We’ve failed to get answers from Facebook and we believe the documents contain information of very high public interest.”

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The seizure is the latest move in a bitter battle between the British parliament and the social media giant. The struggle to hold Facebook to account has raised concerns about limits of British authority over international companies that now play a key role in the democratic process.

Facebook, which has lost more than $100bn in value since March when the Observer exposed how Cambridge Analytica had harvested data from 87m US users, faces another potential PR crisis. It is believed the documents will lay out how user data decisions were made in the years before the Cambridge Analytica breach, including what Zuckerberg and senior executives knew.

MPs leading the inquiry into fake news have repeatedly tried to summon Zuckerberg to explain the company’s actions. He has repeatedly refused. Collins said this reluctance to testify, plus misleading testimony from an executive at a hearing in February, had forced MPs to explore other options for gathering information about Facebook operations.

“We have very serious questions for Facebook. It misled us about Russian involvement on the platform. And it has not answered our questions about who knew what, when with regards to the Cambridge Analytica scandal,” he said.

“We have followed this court case in America and we believed these documents contained answers to some of the questions we have been seeking about the use of data, especially by external developers.”

The documents seized were obtained during a legal discovery process by Six4Three. It took action against the social media giant after investing $250,000 in an app. Six4Three alleges the cache shows Facebook was not only aware of the implications of its privacy policy, but actively exploited them, intentionally creating and effectively flagging up the loophole that Cambridge Analytica used to collect data. That raised the interest of Collins and his committee.

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A Facebook spokesperson said that Six4Three’s “claims have no merit, and we will continue to defend ourselves vigorously”.

The files are subject to an order of a Californian superior court, so cannot be shared or made public, at risk of being found in contempt of court. Because the MPs’ summons was issued in London where parliament has jurisdiction, it is understood the company founder, although a US citizen, had no choice but to comply. It is understood that Six4Three have informed both the court in California and Facebook’s lawyers.

Facebook said: “The materials obtained by the DCMS committee are subject to a protective order of the San Mateo Superior Court restricting their disclosure. We have asked the DCMS committee to refrain from reviewing them and to return them to counsel or to Facebook. We have no further comment.”

It is unclear what, if any, legal moves Facebook can make to prevent publication. UK, Canada, Ireland, Argentina, Brazil, Singapore and Latvia will all have representatives joining what looks set to be a high-stakes encounter between Facebook and politicians.

Richard Allan, vice-president for policy who will testify at the special session after Zuckerberg declined to attend, said the company takes its responsibility around “a number of important issues around privacy, safety and democracy ... very seriously”.